My car is empty after 2 days of fill up is my car fuel economy bad

ANSWER : Your fuel mileage should not be based on time but by how many miles you drive. You should fill the tank completely and mark the miles you have. Drive a couple hundred miles and then fill the tank again and take the miles you drove and divide the gallons to fill the tank to get your mileage per gallon you are getting.

ANSWER : The issue you are having is probably due to an intermittent fault in the starter motor itself or a deficiency in the starter electrical circuit, for example a large voltage drop due to a poor ground or a high resistance connection. These issues can be readily diagnosed and resolved on a mobile basis if you request a hard starting diagnostic. If you request that diagnostic, the responding certified mechanic will get this resolved for you promptly. Based on Toyota’s Factory Service Manual, the battery should not be disconnected if the vehicle engine is running. The battery acts as a large resistive voltage sink and consequently taking the battery out of the circuit, while the alternator is still running, can create a voltage spike on the car’s electrical system which is not good for voltage sensitive components such as the engine computer. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

ANSWER : Hi there. The only mechanical item that might cause the fuel gauge to act this way would be some malfunction within the EVAP vent solenoid system. However, if this occurred right after replacing the instrument cluster, it’s more likely due to an electrical fault that occurred during the installation. I would contact the company or mechanic that completed the instrument cluster installation to ask them if they can take a look at this issue, as it is likely an installation fault and not mechanical.

ANSWER : Hello, thank you for writing in. If the new battery has also failed to hold a charge, the alternator is likely not working correctly. You can test the alternator at home with a voltmeter, or you can remove it and have it tested at most automotive parts stores. It will need to be replaced if it has failed. You will also want to make sure all of the electrical connections are clean, dry, and tight. For more help testing or replacing the alternator, contact our service department to schedule an appointment.

ANSWER : There are reports that the replacement alternators will not communicate with the engine computer and will not charge correctly. I recommend using only the manufacturer approved replacement part. It can be new or remanufactured but approved for use in the vehicle. Some lower cost alternators on the aftermarket will have charging problems since they will not communicate with the ECM on the vehicle and will stop charging.

ANSWER : The acceleration you are experiencing is normal. The car has a large, very powerful engine and was designed to reach 60 MPH in less than 4 seconds which is exceptional. The gas mileage you are reporting is at the lower end of the range reported for this vehicle but it is not extremely low. The EPA city rating is 18 MPG so you are about 10% below the city rating. You can maximize mileage by: keeping the tires adequately inflated; ensuring vehicle wheel alignment is correct; check for stuck brake caliper(s); maintain consistent vehicle speed; make sure engine temperature is in normal range and not too low due to a stuck open cooling system thermostat; and make sure there is no excess weight in vehicle. If mileage does not improve after verifying all of the foregoing, or if you simply want all the foregoing inspected, please request a vehicle fuel efficiency diagnostic and the responding certified mechanic will get this issue investigated and resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you

ANSWER : Check for proper fuel pressure – both while the vehicle is running, and after running. I suspect you will find that fuel pressure is not being maintained in the pressurized portion of the system due to a fuel pressure regulator – which can also leak fuel (o-ring leaking). The inability to maintain proper fuel pressure overnight means the fuel pump has to work longer, while trying to start your engine, to get up to anything close to operating pressure so the engine will fire. Check the fuel filter for clogs as well. A clogged filter will hamper both startup and fuel pressure while driving. A YourMechanic certified technician can perform a Car is hard to start Inspection, or a Car is getting worse gas mileage Inspection, on your vehicle to help diagnose and repair this issue.

ANSWER : Hi there:

The problem with trying to diagnose fuel economy issues is the fact that many variables can cause MPG problems, ranging from driving conditions, driver input, time of year (for winter and summer blends of gasoline) and simple weather conditions. However, in general, dirty throttle body (which wasn’t on your list of services completed), the idle control valve and EGR valve are common components that when dirty or faulty, will negatively impact fuel economy. Before you start to replace or service these parts however, you might want to have a mobile mechanic complete a car is getting poor fuel economy inspection first; so they can inspect your 2003 Kia personally and diagnose the issue for you.